Inflatable structure device and method of inflating same

ABSTRACT

A STRUCTURE DEVICE THAT IS INFLATABLE BY VAPORIZATION OF AN INFLATING MATERIAL, WHICH INCLUDES A BLADDER HAVING POSITIONED THEREIN A WICKING MEANS FOR DISPERSING THE INFLATING MATERIAL AS A LIQUID UPON ENTRANCE TO THE BLADDER TO INCREASE THE SPEED OF INFLATING OF THE STRUCTURE AND A METHOD FOR INFLATING THE STRUCTURE, PARTICULARLY WHERE LOW-PRESSURE INFLATING MATERIALS ARE USED.

Sept. 28', 1971 w. JKMIDDLETON ETAL 3,608,114

INFLATABLE STRUCTURE DEVICE AND METHOD OF INFLATING SAME Filed Jan. 6, 1970 2 Sheets-Sheet 1 INVENTORS WILL/4M J MDDLETO/V EDWARD A. 'POL/TE Sept. 28,1971 w, MIDDLETON ETAL 3,508,114

INFLATABLE STRUCTURE DEVICE AND METHOD OF INFLATING SAME Filed Jan. 6. 1970 2 Sheets-Sheet 2 m u n I II I! II II II 0| II il II II !l I! II II I II llll II I! II II II II In! 2 in! l I i u i l a a 5 f |l||l"|!l|l Ilvi'l Ilrlliil II'IIlavll-I. I

INVENTORS W/LL/AM J M/ODLETO/V. EDWARD A. POL/TE FIG 5 FIG 2 FIG 4 States Patent Cflice 3,608,114 Patented Sept. 28, 1971 3,608,114 INFLATABLE STRUCTURE DEVICE AND METHOD OF INFLATING SAME William J. Middleton, Felton, and Edward A. Polite, Dover, Del., assignors to ILC Industries, Inc., Dover,

Del.

Filed Jan. 6, 1970, Ser. No. 969

Int. Cl. B63c 9/18 US. Cl. 9314 6 Claims ABSTRACT OF THE DISCLOSURE A structure device that is inflatable by vaporization of an inflating material, which includes a bladder having positioned therein a wicking means for dispersing the infiating material as a liquid upon entrance to the bladder to increase the speed of inflating of the structure and a method for inflating the structure, particularly where low-pressure inflating materials are used.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to inflating of expandable closed chambers such as bladders and more particularly to inflating with pressurized gas of inflatable life saving structures such as life vests and life rafts.

Description of the prior art Inflatable structures have depended on high-pressure inflating materials or fluids such as carbon dioxide (CO as the inflating medium because of the ability of such materials to be forcefully released into the structure as a gas or Where any liquid reaches the structure the material is immediately vaporized due to rapid expansion from high pressure so as to inflate the structure. Such structures employ the high-pressure inflating materials for their ability to provide rapid inflation but which, being eflicient under many conditions, can present a hazard to personnel and the structure to be inflated since the container holding the high-pressure inflating material, if under adverse conditions, such as impact, can be exploded by the high pressures used.

Summary of the invention This invention contemplates an effective inflating device and method of inflating the device by providing a bladder construction that has positioned in it a wicking device or means so that a Wickable type inflating material can be quickly dispersed as it enters the bladder from its container so that vaporization of the liquid will be quickly accomplished to provide for an immediate inflation of the device. The invention is particularly advantageous with relatively low pressure type inflating materials since the wicking device provides for the spreading of these materials to effect a more rapid vaporization. Any pressurized inflating liquid maintained under pressure can be used with the invention, however, where the spreading of it will enhance its speed of vaporization.

A bladder construction useful with the present invention can comprise one or more inflatable chambers or bladders, preferably each formed from a plurality of layers of gas impervious flexible sheet-like material sealed together around their outer edges to produce an inflatable enclosure. Each such bladder is provided with one or more inflating material inlet apertures through which the inflating material can enter, when released from a container of the material under pressure that is operatively connected with the bladder inlet aperture.

In accordance with the invention, the device utilizes an inflating material dispersal or wicking means sized to cover a suflicient internal extent of the bladdder to propagate the inflating material as a liquid over large surface areas within the bladder as the material issues into it so as to guarantee continuous movement of the inflating material away from the area of its inlet into the bladder to promote rapid, even volatilization which quickly produces bladder inflation. The wick or wicking means provides for the inflating material to be directed onto it where it can spread rapidly and evenly across the wick and be dispersed therein so the specific surface of the material is extended to present a maximum volatilization area within the collapsed bladder which effects more rapid vaporization for quicker inflation of the device. When the life saving device used is a flotation vest type garment to be worn on the body the wicking means advantageously is positioned therein so as to be capable of absorbing a maximum of radiated and conducted heat from the wearer for transfer to the inflating material as it issues into the bladder to increase further the speed of inflation.

Advantageously the wicking means is provided in the form of a thin flat liquid dispersing web of cellulosic-like material, beneficially in woven or non-woven fibrous form sandwiched between adjacent inner surfaces of the Walls of the bladder. The wicking device can, if desired, extend over substantially the full internal surface area of the bladder for maximizing vaporization therein and is made 'sufficiently dense to provide the very large liquid dispersion surface that carries the inflating material wicked through the bladder, assisted by pressure, so as to speed its evaporation and effect full inflation. The wicking device advantageously can have a configured surface and/or be foraminous with a large number of minute capillarylike passages within and among the fibers to eflect an eflicient wicking of the inflating material in the web so it is rapidly released as a gas from the faces of the web over a large internal surface area of each bladder.

The wicking device is beneficially held from displacement out of a relatively fixed position in which it is ready to distribute the fluid inflating material into the chamber formed between interior surfaces of the bladder by use of attaching means which can be attached to a wall thereof. The attaching means can be, for example, buttons that are heat-sealed at spaced locations to internal surfaces of the bladder and adapted to fasten through mating apertures provided in the wicking device. In the case of a life vest, the attaching means can be advantageously positioned in the bladder at the side designed to be placed against the body so as to provide for positioning the wicking means held close to the wearers body when the device is worn so a maximum body heat is continuously absorbed by the dispersed material over a large area during inflation to increase the inflation speed.

It has been found that when the inflating material is released into the bladder chamber through a distribution means such as a liquid distributing manifold device positioned therein adjacent the wicking device, the inflating material can be directed into forced contact with selected portions of the Web over a substantial surface area of it and the bladder so as to increase the spreading of the material and promote its rapid vaporization. Spaced apart outlet apertures or orifices are located in the manifold so as to direct the inflating material in about parallel spaced jets or sprays issuing therefrom during inflation to effect initial rapid distribution of the material onto the web surfaces on which it spreads to be dispersed and passed off as vapor to inflate the bladder.

For supplying the inflating material into the bladder or bladders of the life saving device a container of inflating material such as, for example, Freon 12, is provided in association with the life saving device which can be a life vest, life raft, inflatable dinghy or the like, and operatively connected therewith through tubing. Means are provided on the container for hand or automatic releasing of the inflating material from its container when inflation is required.

It will be appreciated that the present invention provides for safe storage and effective use, particularly of the low-pressure types of inflating material that have a relatively low vapor pressure at normal and low ambient temperatures, under a wide variety of operational conditions. While the invention reduces the hazards attending use of extremely high-pressure inflating materials or mediums it can also be applied in some cases to any type of liquid inflating material under pressure that is capable of being wicked to provide a more rapid vaporization or evaporation. It also will be appreciated that the invention thus provides more rapid inflating particularly at the relatively low and normal ranges of operating temperatures, of life saving inflatable structures by storing inflating materials at these temperatures and when inflation of a bladder is desired, releasing it in substantial part as a liquid into the inflatable structure and dispersing the material by wicking action over a large area within the structure where the. inflating material then vaporizes quickly and fully to accomplish rapid inflation of the structure.

The above and further objects and advantages of the invention will become more apparent from attention to the annexed drawings and description of the invention that are intended as illustrative and not as limitative of the inventive concepts contained herein.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a partially inflated life vest device embodying the liquid dispersing for rapid inflating of this invention and partly bro-ken away to show one of the wicking devices and its associated fluid distribution manifold;

FIG. 2 is a fragmentary elevational view in section through one of the bladders of the device of FIG. 1 taken along line 2-2 thereof;

FIG. 3 is an elevational view in cross-section of the device of FIG. 1 taken along line 33 thereof and representing in broken lines its fully expanded condition after inflation;

FIG. 4 is a fragmentary elevational view of the front face of one of the inflatable bladders taken along line 44 of FIG. 3 and cut away to show the wicking device of the left bladder extending throughout the chamber; and

FIG. 5 is an enlarged perspective view of the inflating material container, its release mechanism and its outlet line or tubing leading to the life vest.

DESCRIPTION Referring to the annexed drawings, an inflatable life saving device of this invention is shown as a flotation type life vest that has left side, center and right side inflatable bladders 12, 14 and 16 respectively, connected together side by side tomake a wearable garment. For inflating the bladders the life vest is adapted to have associated with it a pressure bottle or container 18 adapted to contain a supply of pressurized liquid inflating material, one example being Freon 12 or a like-acting inflating medium, that can be spread by wicking action when released to a lower pressure atmosphere. The pressure bottle has an actuating mechanism 20' which can be actuated to release its inflating material through a check valve 22 located in a discharge line 24 leading from the bottle, when a lanyard 26 is pulled so as to lift a lever 28 in the mechanism. Lifting of the lever effects puncturing of a seal closing the mouth of the container (not shown) in a known manner thus releasing the charge of inflating material into the discharge line to initiate pressurizing of the life west.

The inflating material discharge line 24 is operatively connected by a union 32, and through a nipple connected thereto, into a manifold-like inflating material distribution header 34 located externally on vest 10 and that is formed from a flexible collapsible tubing, for example, a vinyl plastic. The header extends along the top edge of the life vest retained thereto by partial encasement in a fold of one of the sheets making up the vest. When the inflating material is released from container 18 each of the bladders, which are essentially alike in construction and have like internal parts, can be supplied with inflating material entering the header from the discharge line and passing from the header into its respective tubular off-take connection 36 that also leads into the upper end of a respective tubular downcomer 38, 38a and 38b.

While the description of the bladders 12, 14 and 16 is made herein primarily with reference to the left side bladder 12, since each is substantially alike and has substantially identical connections and parts contained therein, the construction and function of the life vest will be apparent from description and drawings emphasizing bladder 12. Thus, at its lower end downcomer 38 is operatively connected to a tubular inlet connector 40' which enters an aperture in the rear face of the bladder 12 and is sealed thereto by inner and outer annular flanges formed on the connector 40. Connector 40 at its discharge or fluid exit end is in open communication with a manifoldlike fluid distribution tube 42 provided with a row of inflating material exit orifices 44 through which the inflating material can be directed to exit into the bladder where it is dispersed and volatilize'd. Each tube is formed of a flexible plastic material such as a vinyl which can be collapsed with the bladder and is horizontally arranged within the upper curvature of its respective bladder so as to extend substantially the full width of it. This arrangement provides for directing the inflating material in a selected pattern of jets or sprays onto a web-like inflating material dispersing means or wicking device 46 positioned within the bladder '12.

As can be seen from a comparison of the figures, particularly FIGS. 1 through 3, the life vest or structure device 10 has a simplified lightweight construction that provides the separate bladders 12, 14 and 16 by heat sealing together a pair of substantially rectangular plastic sheets that respectively form the front and back walls 48, 50 of the vest. These walls can be constructed, however, of any suitable gas-impervious flexible material, for example, the sheet forming plastic materials that can be heat-bonded such as sheet polyethylene, polyvinylchloride, or like plastics. It will be appreciated that various other gas-impervious fabrics that are heat-sealable or can be sealed together by cementing or the like can be used to form the bladders of the vest such as sheet'rubber, rubberized nylon fabric or the like. Whether by heatsealing or joining together by cementing, the outer edges of the walls 4'8, 50 are thus continuously connected to form a marginal edge seal 52 peripherally around the outer margin of the vest 10 and in two locations vertically of the vest intermediate its right and left ends to form two intermediate seals 54 and 54a. The ends of the latter seals extend into seal 52 so as to divide the vest into three spaced inflatable chambers that respectively form the bladders 12, 14 and 16.

Defined through each of the intermediate seals 54 and 54a and through each vertical left and right end portion of the peripheral seal 52 are lines of six lacing holes 56 all designated by the same numeral. As can be seen, each of the two pairs of six lacing holes that are respectively at right and left sides of the vest, has laced through them one of a pair of shoulder straps 58, 58a that are each retained in place by knotting and available to be tied together at the front as shown for holdin the vest on the wearers body.

When the inflating material is distributed into the bladder 40 from its distribution tube 42 onto the wicking means or device 46 this device provides means to propagate the inflating material by a wicking action, eg capillarity, through the interior of the bladder. The wicking device further distributes and spreads the inflating material that enters as a liquid increasing its specific surface and thus provides for rapid vaporization of the material to increase the speed at which the vest can be inflated. As elsewhere indicated, this is particularly useful with the relatively low vapor pressures produced by inflating mediums such as Freon 12. The upper edge of the wicking device has a central notch which provides for the web to be folded over the top of its distribution tube 42, past inlet connector 40 in a bight and attached to itself by cementing to form a hem which loosely encloses or enwraps the length of the distribution tube. Each wicking device extends throughout the major extent of the interior of its enclosing bladder and defines an upper and lower row of spaced buttonholes 64 by which it is supported in place by engagement therethrough of upper and lower rows of attachment means or plastic buttons 66 arranged to mate with the buttonholes. The buttons are heat-sealed or otherwise attached as indicated at locations 68, for example by cementing, to the inner surface of the front wall 48 of the bladder (see FIGS. 1 through 4).

It will be observed that the exit orifices 44 are positioned in the distribution tube 42, directed downward and outward towards the wicking device 46 so the inflating material issuing therefrom is spread in a line of spaced small liquid streams against the web acting to spread and disperse the material distributed over a sufficient area 9f the web to promote immediate rapid dispersion by wicking away from the entering streams as wicking of the inflating material proceeds through the web for rapid vaporization. It will be appreciated that the wicking effect draws the inflating material away from the area of the exit orifices in substantial part by capillary action, fanning it out and down until vaporization is completed. Where the pressure of the inflating material entering the bladder jets the inflating material onto the wicking device or through it as a liquid onto portions below the exit orifices 44 wicking outward from around each sprayed area occurs which increases the spreading action.

A suitable material for forming the wicking device 46 giving good results has been found to be a paper-like cellulosic fibrous non-woven mat or web in sheet form. The wicking device can be formed, however, of any suitable material in flexible form and have a thickness that provides good wicking of the inflating material.

It is believed that the operation and function of the invention when used to inflate the life vest device 10, will now be apparent. Thus, with the life vest constructed as above and a container 18 charged with an expandable liquid inflating material under pressure and held by means such as a harness (not shown) to the life vest, the union 32 can be connected to the nipple that completes the connection between the container and the manifold 34 which places the vest in readiness to be used when required. When the need arises, the wearer can don the vest and pull the lanyard 26 to operate lever 28 which releases the inflating material into the header 34. The material then flows from the header through the downtake connections 36 into the downcomers 38 and into the fluid distribution tubes 42. From these tubes the pressure of the inflating material as it enters the lower pressure atmosphere within the bladder directs it out of exit orifices 44 onto the wicking device 46 where the wicking action of the fibers therein disperses the discharging inflating material discharging into the bladder through suflicient area of the web to draw the material rapidly away from the exit orifices as a liquid so it can rapidly vaporize from an extended surface in the wicking device in all directions, thus assisting the change of state from liquid to gas for inflating the bladder. It will be appreciated that gravity and the pressure difference of the inflating material entering as a liquid assist to disperse it evenly across the wicking device, thereby presenting a maximum volatilization area within the flotation bladder when collapsed. It should be noted also that this wicking device is held against one side of the inflatable bladder by the buttons 66 heat-sealed to the bladder through the button-holes in the wicking device which provides for the wearers body heat to heat the wicking device and thus the inflating material for more rapid evaporation to quickly inflate the bladder.

It will be appreciated that when the inflating material is Freon 12 or a like-acting material having a relatively low vapor pressure at normal ambient temperatures (e.g. approximately 70 p.s.i.g. at about 70 F.) there is presented a lower hazard of explosion from impact against its container than do other commonly used inflating materials such as CO ordinarily stored at much higher pressures. A relatively safe operational storage and inflation of life vests or the like under a wide variety of ambient temperature conditions is therefore achieved. Freon 12 is a tradename of the DuPont Company for dichlorodifluoromethane, it being understood that similar acting materials may be used. The invention also provides an advantageous wicking dispersion of materials having characteristically higher vapor pressures that can be wicked in inflatable structures, particularly where the structure to be inflated must be folded so that the wicking means provides for passing the inflating material past folds which may otherwise prevent proper bladder inflation.

The present invention has been found to provide satisfactory inflation of a life saving flotation device adequate to support an average sized man by providing a life vest having three inflatable bladders each having an inflated capacity of about 1100 cubic inches when each is pressurized to about 1.5 p.s.i.g. with about two ounces of Freon 12 inflating material stored in a container source as a liquid under its own vapor pressure at about 70 F. ambient temperature. It has been found that with the device and method of this invention such a life vest can be satisfactorily inflated in from about 4 to about 8 seconds from release of the inflating medium from its container when operating at temperatures ranging down to about 30 F. and at lower temperatures when additional means to heat the inflating material is provided.

It will be appreciated that the wicking device or web of this invention can be provided in single or plural form within each bladder and can take various shapes or structures with a continuous or interrupted surface that can be variously configured e.g. undulating. The wicking device can be used either with or without the plural orificed distributing tubes 42. Similarly, these tubes can take various shapes and configurations and extend to greater or lesser extent across or around the wicking device and be variously positioned with respect thereto. Also, additional orificed tubes could be operatively connected with the exit orifices 44 to provide compounding of the paths taken by the inflating material as it is spread onto the web. Also, the exit orifices 44 can be provided at greater or lesser spaced apart locations and be directed at various angles as desired to take various forms such as slots or round or other configured apertures.

With the present invention, one or more of the bladders 12, 14 and 16, as will be appreciated, can have positioned in the wall of it an inflation valve providing for oral inflation of the bladders for emergency use or such oral inflation device could be connected into the header 34. This header can also be provided with check valves toprevent the deflation of all of the bladders if one or more is accidentally punctured,

It will be appreciated that various changes and modifications can be made, all within the scope of the inventive concepts contained herein.

What is claimed is:

1. An inflatable life-saving device for attachment to a wearer and adapted to be inflated by vaporization of a liquid material maintained under low pressure comprising an inflatable bladder means; means operatively connected to said bladder means for attaching the life-saving device to the body of the wearer; liquid material conveying means operatively connected to said bladder means having means therein for connection to a source of liquid inflating material; and wicking means positioned in said bladder means operatively connected to said conveying means for dispersing said liquid inflating material over a large area within said bladder means to speed the inflation of said device.

2. The device of claim '1 in which said bladder means is a plurality of bladders connected together and having said liquid material conveying means operatively connected to each of said bladders.

3. The device of claim 1 in which said wicking means is positioned closer to the wall of the bladder that is adjacent to the body of the wearer when worn to obtain more efiicient expansion of the inflating agent through use of body heat.

4. The device of claim 1 in which said bladder means is formed from a heat-scalable plastic material.

5. The device of claim 4 in which said wicking means UNITED STATES PATENTS 7/1961 Switlik 9316 10/1964 Wyatt 244l17A FOREIGN PATENTS 355,702 10/1921 Germany 9321 MILTON BUCHLER, Primary Examiner P. E. SAUBERER, Assistant Examiner US. Cl. X.R. 

